The invention concerns an arrangement having an electric motor, and in particular having an electronically commutated motor (ECM).
Examples of such motors are shown, for example, in the following documents [of the Applicant] assigned to the assignee of the present application:
It would not be possible to reproduce the extensive content of these documents even in summarized form, and reference is therefore made to their complete contents.
It is an object of the invention to make available a new arrangement and a new method for controlling an electric motor.
According to the invention, this object is achieved by connecting an output signal of a microprocessor, which can take on either a high level or a low level, to a voltage divider which regulates motor current, and varying the microprocessor output signal to achieve a desired motor current characteristic curve. [the subject matter of claim 1]. It is possible thereby, in program-controlled fashion, either to extend acceleration (called a xe2x80x9csoft startxe2x80x9d) or to make acceleration as short as possible by raising the operating point for the current control system during the acceleration period so that the motor current can be higher during acceleration than later in normal operation.
A preferred method is to set a motor current limit to a first value for motor startup, to monitor the startup, and to reset the motor current limit to a second value after startup. [the subject matter of claim 11]. This method can be flexibly adapted to the needs of a user, since the limiting values can be adjusted in program-controlled fashion.
Another manner of achieving the stated object is the subject matter of claim 23. In this fashion, it is easily possible to adapt this kind of arrangement having an electric motor to the needs of its user by entering the desired values via the interface into the nonvolatile memory element of the arrangement (or reading it out from said memory element). This applies in principle to all motor values, e.g. rotation speed, current limiting values, temperature, acceleration time, torque at rest, and others. The storage operation can be accomplished at the factory or at a later point in time in order to adapt the motor optimally to a customer""s needs. This is particularly advantageous for motors that drive a fan, since with such fans the needs of users can be very different, and a fan arrangement of this kind can very easily be optimized for a user""s needs, as depicted for example in FIG. 22.
Further details and advantageous developments of the invention are evident from the exemplary embodiments described below and depicted in the drawings (and to be understood in no way as a limitation of the invention).